Electric heater



FIG. 1 is a perspective view of the electric heater;

FIG. 2 is a front elevational view of the electric heater;

FIG. 3 is a left elevational view of the electric heater; and,

FIG. 4 is a rear elevational view of the electric heater.

We claim the ornamental design for the electric heater, as shown anddescribed.